title: Meningococcal disease and polymorphism of FcgammaRIIa (CD32) in late complement component-deficient individuals.
abstract: Late complement component-deficient (LCCD) individuals lack plasma bactericidal activity and are highly susceptible to meningococcal disease. Phagocytosis plays a significant role in immune defence against meningococci and involves FcgammaRIIa (CD32) on leucocytes. Two allotypic forms are currently recognized: FcgammaRIIa-R131 and RIIa-H131. Neutrophils with the IIa-H/H131 allotype are more effective in phagocytosis than IIa-R/R131. We studied the distributions of IIa-R131 and IIa-H131 allotypes among 29 Russian LCCD patients who had suffered from recurrent episodes of meningococcal disease. The distribution of IIa-R/R131 to heterozygous IIa-R/H131 to homozygous IIa-H/H131 genotypes was 0.14:0.29:0.57 for LCCD patients who developed the first episode of disease before 10 years of age. The distribution was 0.21:0.64:0.14 for patients who experienced meningococcal disease above the age of 10 years (chi2 = 6, P < 0.05, odds ratio for IIa H/H131 versus R/R131 = 8). Meningococcal disease had a 'grave' course in 14 of 31 disease episodes in patients with IIa-R/R131 and IIa-R/H131 allotypes, in contrast to 1 of 18 episodes in patients with IIa-H/H131 allotype (chi2 = 7, P < 0.01, odds ratio = 14). We conclude that IIa-H/H131 individuals appear to have a higher acquired antibody-mediated phagocytosis-dependent resistance to meningococcal disease above the age of 10 years. Additionally, effective CD32-mediated phagocytosis may restrict the severity of meningococcal disease in LCCD patients with IIa-H/H131 phenotype.
authors.affiliation: Central Institute of Epidemiology, Moscow, Russia.
authors.forename: A E
authors.initials: AE
authors.lastname: Platonov
authors.forename: E J
authors.initials: EJ
authors.lastname: Kuijper
authors.forename: I V
authors.initials: IV
authors.lastname: Vershinina
authors.forename: G A
authors.initials: GA
authors.lastname: Shipulin
authors.forename: N
authors.initials: N
authors.lastname: Westerdaal
authors.forename: C A
authors.initials: CA
authors.lastname: Fijen
authors.forename: J G
authors.initials: JG
authors.lastname: van de Winkel
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003165:Complement System Proteins / Q000172:deficiency* / Q000235:genetics / Q000276:immunology; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008589:Meningococcal Infections / Q000235:genetics* / Q000276:immunology; D011110:Polymorphism, Genetic; D017452:Receptors, IgG / Q000235:genetics*
chemical_list: D017452:Receptors, IgG; D003165:Complement System Proteins